7/07/2010 @ 2:00PM

In Pictures: The World's Richest Royals

Prince Albert II, Monaco

Fortune: $1 billion (unchanged)

Age: 52

Head of 700-year-old Grimaldi family attempting to add onto Monaco, which is smaller than New York’s Central Park, by erecting new district on pillars at sea. Promoting his new film Antarctica 2009: A Continent in a State of Alert, based on his 17-day trek there. In June long-time bachelor announced engagement to former South African Olympic swimmer Charlene Wittstock. Being sued by former employee Robert Eringer, an alleged spymaster for Monaco, for back pay. Family fortune includes real estate, art, antique cars, stamps and stake in Monte Carlo’s casino.